Method of waterproofing paper, cloth or fur and products produced thereby



qwwgy METHOD OF WATERPROOFING PAPER. CLOTH OR FUR AND PRODUCTS PRODUCED THEREBY Filed Oct. 3, 1956 Fl 6. l,

Feb. 17, 1959' PETRENKO Q 2,874,075

SOLUTION SOLUTION LEAD ACETATE POTASSIUM O ALUM.

SOLUTION PRECIPITATE LEAD SULFATE.

SOLUTION APPLIED TO- PAPER WEB CLOTH 0R F i INVENTOR ALEXANDER M.PETR EN|- Q ATTORNEYS U i d S ate P en 07 cc METHOD OF WATE ROF ING PAPER, CLOTH OR FUR AND rnonuc rsrnonucan THEREBY Alexander M. Petrenko, Pai-is, France, assignor to Petren Products 'Inc., York,'Pa., a corporation of D elawar'e Application October 3, 1956, SerialNo. 013,600

8 Claims. (,Cl- 117-'14 0) This invention relates to a process for the preparation of aliquid which" when applied will render'pa er and paper products, cloth, leatherjw'ood, jute and jute products Waterproof. Also applied to furs and fabrics, it makes the same waterproof and acts 'additionally'as a protection against moths'and similar insects.

Heretofore water repellent papers have been prepared by applying many types of'sizings, one ofwhich is known as Aqu'apel and consists in'si'z i'ng' the paper with an alkylkete'ne dimer. Various other't'ypes" of s'izings'using cla'y, starch, alum'and other agents have been extensively used. All of these processes coat the-Tsurfaee of'the paper web so as to improvethesurfa'ce texture thereof and form a barrier over the fiber'weh'that is more or less resistant to water. None of these processes impart a degree of water repellency to'the cellulose fiber itself. All of the prior processes'treat the surface of the web and not the fiber, which goes to constitute th'e'web'.

It is an object of the process ofthis invention to produce a waterproof paper. I 'It is also an object'offthis invention to impregnatethe' fibers of the paperwith a material that willfi'nipa'rt to the fibers themselves awat er repeileney; and thereby produce' a waterproof product? T A It is also an object lf'this inventionto produce a process that will treat cloth, ieather,'wood"and jute to render the samewaterproof. 5 A further object of this invention is to provide a treatment for furs and wool materialsthat 'w'ill'render the same waterproof ahd repellent tomoth's and other insects.

"The various features of novelty which'char'acterize' this invention are pointed out with particularity in the claims annexed to'and'forming part of this specification; Fora better understanding of the special obiectsfob'tained by its use, reference should 'be had to thespecificati'on and examples therein in which is illustrated and described the preferred embodiment of this'inventior Fig. 1 is a flow sheet showin'g"the' preparation of the twos'olutions, the mixing of the solutions, the separation of the precipitated lead sulphateandthe application of 'thefinal solution 'to paperweb, cloth strut;

Fig.2 is an enlarged view 6 a cloth impregnated with the solution.

Fig. 3' is a sectional view onlineS-S of Fig. 2 and shows the impregnation within'the fiber of the cloth.

Briefly, this invention comprisesfthe preparation of a solution, the components of'which "are critical} and the application of this solution to the fiberweb duringthe process of manufacture of paper, or to the'paper after it has been manufactured. i

Two solutions are prepared; one, a solution of lead acetate is prepared by dissolving 481 grams of lead acetate in 500 cc. of water at normal roomtemperature in the neighborhood of 70 F. to8 0, A second solution is prepared by dissolving 32 grains of potassiumalum (neutral) in 500 cc. of water. These'two' solutions arethen mixed and allowed to stand until the precipitated lead sulphate has settled. The clear liquidis dec'anted "and used in the following processes. V

' The above solution is prepared so that there aretwo parts of alum to three parts of lead acetate by weight. The final solution on mixing must have '80 "parts of the combined chemicals to one thousand parts of water to obtain the optimum results, but may vary from 6 0 to- 102 2 parts as explained below. It is not necessary to use Q. P; chemicals as technically puregrade commercial chemicals may beemployed. Thelead acetate must be the neutral salt. I

The lead acetate and the alum as pointed out above are used in the ratioof 48 grams of lead acetate to 32 gramsof alum to give the' optimum result. These may be varied; the lead acetate being as low as 30 grams and as high as grams, and the neutral potassium alum may be as low as 30 grams and as high as 47 grams. Each dissolve in 500 cc." of water so that'the final solution will be in'the'neighb'orhood of one liter/ While the above proportions give the optimum results,

- it is possible'to va'ry these proportions to give some degree of waterproofing. For-example, equal-proportions of lead acetate and alumgive a degree of waterproofing, but this is not comparable to the results obtained by "using the three parts of lead acetate to two parts of alum.

The above solution is normally applied by means of'a perforated pipe or spray device of any 'type that will equally distribute'the' solutionacross the paper'during its manufacture, or the paper web may be immersed in abath of the solution. The paper must not contain an excessive amount of water at the time of the application of this solution and the paper must be sufliciently dry as it leaves the last roller, so that the cutting machines will operate effi'ectively, the' drying being performed by normal means, such as by steam heated or flame heated rollers.

The'process as set forth in this application comprises the treatment of the fibers with the'solution. Any sizing or other process that prevents the solution from entering the fibers through the pores thereof should be avoided.

While in the above application, the solution is applied to the paper web during the manufacture thereof, it may also be applied to the paper after the paper has left the original manufacturing plant, in which case it is desirable Running water or; an inclined surface KRAFT PAPER; 280 GRAMS Waterproofed paper Ordinary paper Dry Wet Dry Wet; I

Time Necessary to With. Discontinued 2 minutes.

aiter31mi1iutes. Mullen 3.9 0.8 3.5 0.9. Rupture 1, 238 323 1, 235 390.

KRAFT PAPER, 224 GRAMS Time Necessary to Wet. Discontinued lminute. v after 31 min- 7 IMITAIION' LEATHER PA'PER,.280GRAMS Time Necessary to Wet. Discontinued Emtnute's.

' atterBlmlnutes. Mullen 2.5 0.600 0.200.

Rupture ta en ed eb- 17. 39.

the resistance to wetting and the comparative physical-- properties of different typesfof paper after waterproofing and, before waterproofing These tests show that the different types of paperiwere wet within 2 minutes-"l minute and 5 minutes respectively, while none of the samples that had been waterproofed were wet within the 31 minutes before the test was discontinued.

A second test was run on the same paper setting forth the time required for water to penetrate the waterproof paper when folded and holding 100 grams of water; and its resistance to mullen perforation after six hours, and thirty minutes test:

EXAMPLE H A' solution was prepared having 48 grams of lead v acetateand 32 grams of alum per liter, and the clear solution decanted from the precipitated material. This solutionwas used to waterproof a sample of military khaki clothing-measuring 1.46 meters by 1.1 meter ap proximately, by immersing the sample in the solution and'then drying the same. This sample was tested as follows in an ofiicial laboratory:

The' cloth was stretched on a wooden frame and exposed to the action of falling rain at various inclinations from degrees to 70 degrees, the amount of water being approximately 2 liters per minute per square meter, and the exposure continued for a period of one week without interruption.

It was found that the unexposed surface did not present any trace of Water after the test had been completed.

EXAMPLE III Another test also conducted to determine the eifectiveness of the waterproofing as applied above by determining the height of a column of water necessary to force the water through the cloth. Untreated samples withstood a pressure of 5 centimeters while the two treated samples withstood a pressure of 17 centimeters to 14 centimeters respectively.

Furs and natural fabrics also may be treated with this solution to render them waterproof by wetting them with the solution and then drying them. It has been found that the articles so treated are not subject to the attack of moths.

' In the foregoing specification, the term we refers -to'the endless sheet of paper coming from the paper machine in its full width, or from a roll of paper in a converting operation.

The term alum designates the neutral double salt of aluminum sulphate and potassium sulphate and does not refer to aluminum sulphate.

There are many advantages in waterproofing the fibers of a paper web as it prevents the paper from absorbing water, losing its strength and disintegrating. This is particularly true of the straw papers and the commonly used kraft papers. The process of this invention is an inexpensive method of rendering the fibers waterproof -and eliminates the necessity for sizing unless such sizing is used exclusively for increasing the strength.

Another advantage of the waterproof paper produced by this process is that a package made from a paper of sufiicient density and thickness will prevent the contents of the package from absorbing moisture.

This process has been used to waterproof cloth which will not allow the fibersto absorb water and will prevent the growth of mold spors and has been found exceptionally satisfactory for sail cloth, tents, etc.

While in accordance withv the provisions of the statute there has been illustrated and described the best form of embodiment of the invention, it will be apparent to those skilled in'the art that changes may be made in the process disclosed without departing'from the spirit of this invention as set forthin the appended claims, and that in some cases certain features of this invention may be used to advantage withouta corresponding use of otherfeatures.

What is claimed is: r

1. A method of waterproofing a paper web which comprises; preparing a solution containing 32 parts of alum and 500 parts of water; preparing a second solution containing 48 parts of lead acetate and 500 parts of water; mixing these two solutions, separating the precipitate and treating said paper web with the clear solution, and drying the same.

2. A method of waterproofing the fibers of a paper web which comprises; preparing a solution containing 30 parts to parts of lead acetate to 500 parts of water; preparinga second solution containing 30 parts to 47 parts of neutral potassium alum to 500 parts of water; mixing these two solutions, separating the precipitate and treating said, paper web with the clear solution, and drying the same.

3. A method of waterproofing the fibers of a paper web, which comprises; preparing a solution containing 30 parts to 55 parts of lead acetate to 5700 parts of water; preparing a second solution containing 30 parts to 47 parts of neutral potassium alum to 500 parts of water; mixing these two solutions, said solution before mixing having 80 parts of combined chemicals, mixing these solutions, separating the precipitate and treating said paper web with the clear solution, and drying the same.

4. A method of waterproofing natural fiber fabric which comprises; preparing a solution containing 30 to 35 parts by weight of lead acetate dissolved in water; preparing, a second solution containing 30.to 37 parts by weight of neutral'potassium alum dissolved in a further quantity of water to make a total of approximately 1000 parts by weight of water when mixed; mixing these two solutions, separating the precipitate and treating said fabric with the clear solution, and drying the same.

5. A method of treating furs and natural fabrics to render them waterproof and moth repellent, which comprises; preparing a solution containing 30 to 35 partsby weight of lead acetate dissolved in water; preparing a second solution containing 30 to 37 parts by weight of neutral potassium alum dissolved in a further quantity of Water to make a total of approximately 1000 parts by weight of water when mixed; mixing these two solutions, separating the precipitate and impregnating the material and drying the same.

'6. A waterproof fibrous material having within the pores of the fibers a soluble reactant product of two parts neutral potassium alum and three parts lead acetate.

7. A method of treating a felt product to render the same waterproof and moth repellent, which comprises;

preparing a solution containing 30 to 35 parts by weight a solution comprising dissolving between 30 and 47 parts by weight of alum inwater, dissolving between 30 and .5 55 parts by weight of lead acetate in a further quantity of water, mixing the two solutions, adding water to make approximately 1,000 parts total weight of water, sepa rating the precipitate and treating said paper web with the clear solution and drying the same.

References Cited in the file of this patent UNITED STATES PATENTS 644,250 Kipling et al Feb. 27, 1900 6 Menzies Ian. 7, 1902 Goldhammer Feb. 6, 1940 Schwartz Mar. 25, 1941 Bryce I an. 27, 1942 Quarles et al Dec. 25, 1945 Thurmon Sept. 29, 1953 McLaughlin et a1 Apr. 30, 1957 

1. A METHOD OF WATERPROFING A PAPER WEB WHICH COMPRISES; PREPARING A SOLUTION CONTAINING 32 PARTS OF ALUM AND 500 PARTS OF WATER; PREPARING A SECOND SOLUTION CONTAINING 48 PARTS OF LEAD ACETATE AND 500 PARTS OF WATER; MIXING THESE TWO SOLUTIONS, SEPARATING THE PRECIPITATE AND TREATING SAID PAPER WEB WITH THE CLEAR SOLUTION, AND DRYING THE SAME. 